a few LED's no longer light up [solved]

;D  paul, i solved it!

since the voltage at OA was abnormal, i looked closely at the board.  looking from the top, i noticed that 2 solder points at the MJE5731A transistor were touching by a very, very minute amount, so i got out a syringe needle and scraped it a tiny bit so that they were separated and that did it. 

the voltages are now as follows.  the LED's now light up  8) .

IA  118.1
IB  118.0
OA  106.8
OB  107.7
BA  0
BB  0

thanks again for your help paul, GREATLY APPRECIATED ;) .
 
wesleyHK said:
;D  paul, i solved it!

since the voltage at OA was abnormal, i looked closely at the board.  looking from the top, i noticed that 2 solder points at the MJE5731A transistor were touching by a very, very minute amount, so i got out a syringe needle and scraped it a tiny bit so that they were separated and that did it. 

the voltages are now as follows.  the LED's now light up  8) .

IA  118.1
IB  118.0
OA  106.8
OB  107.7
BA  0
BB  0

thanks again for your help paul, GREATLY APPRECIATED ;) .

Glad you and PB were able to solve this.  These sorts of posts are very helpful to those of us starting out.  Thanks. 
 
airdronian said:
wesleyHK said:
;D  paul, i solved it!

since the voltage at OA was abnormal, i looked closely at the board.  looking from the top, i noticed that 2 solder points at the MJE5731A transistor were touching by a very, very minute amount, so i got out a syringe needle and scraped it a tiny bit so that they were separated and that did it. 

the voltages are now as follows.  the LED's now light up  8) .

IA  118.1
IB  118.0
OA  106.8
OB  107.7
BA  0
BB  0

thanks again for your help paul, GREATLY APPRECIATED ;) .

Glad you and PB were able to solve this.  These sorts of posts are very helpful to those of us starting out.  Thanks.

you're more than welcome.  with a few builds under my belt, i thought i wouldn't encounter any problems, boy was i wrong.  life is about learning, no matter how old we are.



 
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